Why does the n8n Google Sheets node repeat first sheet data when given multiple sheet names?

Below is some insight into what is happening and how to resolve the issue:

Is the Node Running Once Per Input?

Yes – under normal conditions, when you pass multiple items into a node, n8n will execute the node once per input item. In your case, the expectation is that the Google Sheets node will run separately for the sheet named "ONE" and then for "TWO."

Why Only Data from the First Sheet?

Even though multiple input items are received, what often happens is that the dynamic field (in your case, the sheet name) isn’t being re‐evaluated for each item. Instead, the parameter value is being set once (usually when you configure the node) and then reused for all input items. This means that if the first input item was “ONE” at the time you configured (or tested) the node, the node ends up fetching data only from that sheet each time.

What to Check and How to Fix

1. Dynamic Expression:
   Verify that the field where you specify the sheet name is set up using an expression (for example, using {{ $json.sheetName }} or similar) so that it picks up the value from each input item. If the field is statically set, it will not update per item.

2. Node Execution Mode:
   Confirm that the node is set to run per input item rather than “Run Once for All Items.” Sometimes, if you return an array and the node is configured with “Run Once for All Items” then the parameter is taken only from the first element of the incoming data.

3. Refresh Parameters if Needed:
   In some cases further along in the setup (for example with mapping or cached column information), you might need to re-open the node settings so that the dynamic evaluation is reset.

Example Check for the Sheet Name Field

If you are receiving your sheet names from the previous Code node, ensure that in your Google Sheets node the sheet name field is set up like this:

TEXTCopied
={{ $json.sheetName }}

Or if your output key is different, replace sheetName with the proper key. This tells the node to use the current item’s value rather than a preset value.

Summary

• The Google Sheets node is executing once per input item in n8n.
• The repetition of data (from sheet “ONE” for every item) indicates that the dynamic sheet name is not being properly applied for each item.
• Ensure that the sheet name parameter is set with an expression so that it dynamically reflects each input (and that the node is configured to run per item rather than all at once).

Adjusting these settings should have the node pick up “ONE” and then “TWO” as separate dynamic inputs and merge their results as expected.